Various protocols in biological or chemical research involve performing a large number of controlled reactions on local support surfaces or within predefined reaction chambers. The designated reactions may then be observed or detected and subsequent analysis may help identify or reveal properties of chemicals involved in the reaction. For example, in some multiplex assays, an unknown analyte having an identifiable label (e.g., fluorescent label) may be exposed to thousands of known probes under controlled conditions. Each known probe may be deposited into a corresponding well of a microplate. Observing any chemical reactions that occur between the known probes and the unknown analyte within the wells may help identify or reveal properties of the analyte. Other examples of such protocols include known DNA sequencing processes, such as sequencing-by-synthesis (SBS) or cyclic-array sequencing.
In some conventional fluorescent-detection protocols, an optical system is used to direct an excitation light onto fluorescently-labeled analytes and to also detect the fluorescent signals that may emit from the analytes. However, such optical systems can be relatively expensive and involve a relatively large benchtop footprint. For example, such optical systems may include an arrangement of lenses, filters, and light sources.
In other proposed detection systems, the controlled reactions occur on local support surfaces or within predefined reaction chambers provided over an electronic solid-state light detector or imager that does not involve a large optical assembly to detect the fluorescent emissions. However, such proposed solid-state imaging systems may have some limitations. For example, fluidically delivering reagents (e.g., fluorescently-labeled molecules) to the analytes that are located on the electronic device of such systems may present challenges. In some scenarios, the reagent solution may breach the electronic device and corrode components thereof, for example.